I agree with Spartacus that it will be private money and private money only that will save a Retractable for the Caps. Otherwise it'll be a dome till the place is torn down and the Caps will have to accept that.
Heaven knows where that private money would come from, so I'm skeptical.
Grass is out of the question for BC Place for the same reason grass is out of the question for Rogers Center: too many trade shows and conventions and other events that need the turf to be removed.
That is why Rogers Center and BC Place use "Convertible" Fieldturf. It comes in square sections to be easily removed.
Look at the turf the Blue Jays play on. It's in square sections 6 feet aside.
Our turf is the same turf the Expos played on when they left Montreal in 2004; Olympic Stadium sold it to BC Place for $ 1.5 million.